I am interested in quaternionic-Kahler metrics that are "as inhomogeneous as possible."

Every complete quaternionic-Kahler manifold $X$ I can remember hearing of is a discrete quotient of some $Y$, such that $Isom(Y)$ contains a nontrivial connected Lie group. Are there any known examples of complete quaternionic-Kahler $X$ that don't arise in this way?

(By "quaternionic-Kahler manifold" I mean one with holonomy contained in $Sp(n)Sp(1)$ but *not* in $Sp(n)$ -- in other words, I want to exclude the hyperkahler case.)